Pin and clevis-type shackles that include a lock for preventing unwanted disengagement of the pin from the clevis are disclosed by the following U.S. patent numbers: U.S. Pat. No. 2,097,465, granted Nov. 2, 1937, to William D. Morrison; U.S. Pat. No. 3,754,418, granted Aug. 28, 1973, to Peter B. Miller; U.S. Pat. No. 4,423,610, granted Jan. 3, 1984, to Judy L. Hart and William A. Munday; and U.S. Pat. No. 5,114,260, granted May 19, 1992, to Judy L. Hart and William A. Munday. These patents should be considered in order to put the present invention into proper perspective.
With pin-and-clevis type shackles, it is desirable to have a clevis that easily can be locked and unlocked. It also is desirable that the shackle be assembled easily, yet be durable in structure. The present invention is directed to such a shackle.
Our prior U.S. Pat. No. 5,114,260 discloses a pin-and-clevis shackle having a lock mechanism. The lock mechanism includes a lock member that is biased into a lock position by a leaf spring. The lock member includes a pair of rounded side portions that act as handles to assist in retracting the lock member into an "unlocked" position, against increasing resistance of the leaf spring. The present invention is an improvement upon this design.